U.S. patent number 5,963,010 [Application Number 08/961,421] was granted by the patent office on 1999-10-05 for battery controller for controlling batteries of different kinds and including battery monitoring means for calculating remaining operation time and an information processing apparatus including such battery controller.
This patent grant is currently assigned to Clevo Co., Hitachi, Ltd.. Invention is credited to Will Chen, Yoshihiro Hayashi, Thomas Kao, Satoshi Ozeki.
United States Patent |
5,963,010 |
Hayashi , et al. |
October 5, 1999 |
Battery controller for controlling batteries of different kinds and
including battery monitoring means for calculating remaining
operation time and an information processing apparatus including
such battery controller
Abstract
A battery controller for controlling at least two batteries of
different kinds, includes a kind-of-battery detection unit for
detecting a kind of battery, and a battery switching unit in which
a switching voltage, a suspended mode shift voltage and a
termination voltage having different values in accordance with the
kind of the battery detected by the kind-of-battery detector are
previously set to compare an output voltage of a battery being
discharged with the previously set switching voltage, suspended
mode shift voltage and termination voltage so that switching of the
battery being discharged, stopping of operation of an apparatus
being supplied with electric power by the battery being discharged
or stopping of supply of electric power by the battery being
discharged is performed.
Inventors: |
Hayashi; Yoshihiro (Sagamihara,
JP), Ozeki; Satoshi (Ebina, JP), Kao;
Thomas (Hsin-Chuang, TW), Chen; Will (Taoynan,
TW) |
Assignee: |
Hitachi, Ltd. (Tokyo,
JP)
Clevo Co. (TW)
|
Family
ID: |
17736476 |
Appl.
No.: |
08/961,421 |
Filed: |
October 30, 1997 |
Foreign Application Priority Data
|
|
|
|
|
Oct 31, 1996 [JP] |
|
|
8-288917 |
|
Current U.S.
Class: |
320/106;
320/110 |
Current CPC
Class: |
H01M
10/4257 (20130101); G01R 31/3648 (20130101); H01M
10/482 (20130101); H02J 7/00036 (20200101); H02J
7/00047 (20200101); H02J 7/0024 (20130101); H01M
10/4221 (20130101); H01M 6/5044 (20130101); G01R
31/3835 (20190101); Y02E 60/10 (20130101) |
Current International
Class: |
H02J
7/00 (20060101); H01M 10/42 (20060101); H01M
10/48 (20060101); G01R 31/36 (20060101); H01M
6/00 (20060101); H01M 6/50 (20060101); H01M
010/46 () |
Field of
Search: |
;320/106,110,119,132,136,149,153,FOR 114/ ;320/FOR 129/ ;320/FOR
134/ ;320/FOR 138/ ;320/FOR 142/ ;320/FOR 147/ |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Tso; Edward H.
Attorney, Agent or Firm: Fay, Sharpe, Beall, Fagan, Minnich
& McKee
Claims
We claim:
1. A battery controller for controlling at least two batteries of
different kinds, comprising:
kind-of-battery detection means for detecting a kind of battery;
and
battery switching means in which a switching voltage, a suspended
mode shift voltage and a termination voltage having different
values in accordance with the kind of the battery detected by said
kind-of-battery detection means are previously set to compare an
output voltage of a battery being discharged with said previously
set switching voltage, suspended mode shift voltage and termination
voltage so that switching of the battery being discharged, stopping
of operation of an apparatus being supplied with electric power by
the battery being discharged or stopping of supply of electric
power by the battery being discharged is performed.
2. A battery controller according to claim 1, comprising:
battery charging means for charging the batteries of various kinds
in combination of constant current charging and constant voltage
charging; and
charge control means for controlling said battery charging means in
accordance with the kind detected by said kind-of-battery detection
means.
3. A battery controller according to claim 1, wherein said
kind-of-battery detection means measures an impedance of a
thermistor terminal of each battery to thereby detect the kind of
the battery.
4. A battery controller according to claim 1, wherein each of the
batteries includes a thermistor terminal, a battery voltage
terminal and a battery monitoring IC.
5. A note-type personal computer including a battery controller for
controlling at least two batteries of different kinds,
comprising:
kind-of-battery detection means for detecting a kind of battery;
and
battery switching means in which a switching voltage, a suspended
mode shift voltage and a termination voltage having different
values in accordance with the kind of the battery detected by said
kind-of-battery detection means are previously set to compare an
output voltage of a battery being discharged with said previously
set switching voltage, suspended mode shift voltage and termination
voltage so that switching of the battery being discharged, stopping
of operation of an apparatus being supplied with electric power by
the battery being discharged or stopping of supply of electric
power by the battery being discharged is performed.
Description
BACKGROUND OF THE INVENTION
The present invention relates to a battery controller for
controlling batteries of different kinds and more particularly to a
battery controller for controlling batteries of different kinds
which are equipped in a portable information processing apparatus
or communication apparatus. Further, the present invention relates
to a note-type personal computer equipped with the battery
controller.
Conventional apparatuses such as note-type personal computers,
portable telephones, portable cassette players and handy video
cameras include a battery for supplying electric power to internal
circuits provided in the apparatuses when an external power supply
is not connected thereto.
A battery used in the portable information processing apparatus or
the like includes a NiCd battery, a NiMH battery or a Li ion
battery.
The NiCd battery uses nickel for a positive pole and cadmium for a
negative pole and has excellent low temperature characteristic and
overcharge/overdischarge resistant characteristic. Further, the
NiCd battery has a long life and a low manufacturing cost but has
problems such as a large memory effect, a low electric power
capacity per unit weight and environmental disruption due to
cadmium.
The memory effect is one of characteristic of a secondary battery
which can be re-charged. When the battery is re-charged in the
state where electric power in the battery is not discharged
completely, the battery memorizes the charge level remaining
therein upon the re-charging operation and when the charge level
remaining upon the re-charging operation is reached in the
re-discharging operation, the battery stops the discharging
although electric power in the battery is not discharged
completely.
The NiMH battery uses nickel for a positive pole and
hydrogen-occluding alloy for a negative pole and has a larger
electric power capacity per unit weight and a smaller memory effect
as compared with the NiCd battery.
The Li battery uses material which occludes and emits lithium ions
in positive and negative poles and generally uses LiCoO.sub.2 for
the positive pole and carbon for the negative pole.
The Li ion battery has an excellent feature that the electric power
capacity per unit weight is larger than the NiMH battery and there
is no memory effect, while since the Li ion battery has cobalt
contained in the positive pole thereof, it is difficult to reduce a
manufacturing cost of the positive pole and a peripheral circuit
for preventing reduction of the safety and deterioration of the
performance upon the overcharging operation is indispensable for
the Li ion battery.
Further, various batteries used in the conventional portable
information processing apparatus or the like have different
charging and discharging characteristics.
More particularly, a constant-current charging system is used to
charge the NiMH battery. The NiMH battery is charged by a rapid
charging current recommended by a battery maker and a temperature
of the battery is detected at a thermistor terminal thereof to
finish the charging.
In addition, a constant-current and constant-voltage charging
system is used to charge the Li ion battery. In the
constant-current and constant-voltage charging system, the battery
is first charged by a constant current and when a terminal voltage
of the battery reaches a predetermined value, the battery is
switched to be charged by a constant voltage and then after an
elapse of predetermined time the charging is finished.
As different points of the discharging characteristics of the NiMH
battery and the Li ion battery, a very low battery voltage and a
final or termination voltage are different.
The very low battery voltage is a voltage at which an apparatus
equipped with the battery is shifted to a suspended mode. In
portable personal computers or the like, the operation mode is
shifted to the suspended mode when this voltage is reached, to
prevent stoppage of supply of electric power.
Further, the termination voltage is a voltage for stopping supply
of electric power by the battery. Since there are any cells in
which discharging is insufficient when the termination voltage is
too high and which is overdischarged when the termination voltage
is too low, it is necessary to set the termination voltage
carefully.
In the conventional portable information apparatus or the like, the
charging and discharging characteristics are largely different
depending on a kind of a battery mounted therein and accordingly
the apparatus cannot use a battery of different kind.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a battery
controller capable of effectively utilizing the capacity of
batteries of various kinds and preventing overcharging.
It is another object of the present invention to provide a battery
controller capable of charging batteries of various kinds.
It is another object of the present invention to provide a battery
controller capable of calculating a total remaining operation time
of a plurality of batteries.
These and other objects and novel features of the present invention
will be apparent from the following description of the
specification and the accompanying drawings.
Brief description of representative aspects disclosed in the
present invention is as follows:
(1) In the battery controller for controlling a plurality of
batteries of various kinds simultaneously, electric power is
supplied to an apparatus connected to the batteries while switching
the plurality of batteries of different kinds.
The battery controller examines whether batteries are mounted in
slots in which the plurality of batteries of various kinds can be
mounted and when batteries are mounted in the slots, the kind of at
least two batteries mounted in the slots is detected by
kind-of-battery detection means.
For example, when the batteries mounted in the slots include
thermistor terminals indicating temperature of the batteries, the
kind-of-battery detection means of the battery controller measures
impedances of the thermistor terminals to detect the kind of the
batteries.
Discharge switching means of the battery controller stops using of
a battery being discharged currently and starts to discharge
another battery. The discharge switching means is supplied with the
kind of battery detected by the kind-of-battery detection means and
an output voltage of the battery being discharged.
The discharge switching means examines in accordance with the kind
of battery detected by the kind-of-battery detection means whether
the output voltage of the battery being discharged reaches a
previously set battery switching voltage which is different
depending on the kind of battery.
As the result that the discharge switching means examines the
output voltage of the battery being discharged, when the output
voltage of the battery being discharged reaches a battery switching
voltage, the battery being discharged is switched.
Further, when the other battery is not mounted in case where the
battery being charged is switched, the battery continues to be
discharged even after the output voltage of the battery reaches the
battery switching voltage. The discharge switching means examines
in accordance with the kind of battery detected by the
kind-of-battery detection means whether or not the output voltage
of the battery being discharged reaches the previously set
suspended mode shift voltage which is different depending on the
kind of battery.
As the result that the discharge switching means examines the
output voltage of the battery being discharged, when the output
voltage of the battery being discharged reaches the previously set
suspended mode shift voltage, the signal for shifting an apparatus
including the battery controller to the suspended mode is
produced.
When the apparatus including the battery controller is an
information processing unit having the suspended mode and the
apparatus receives the signal for shifting the apparatus to the
suspended mode from the battery controller, the apparatus stops
usual operation and is shifted to a mode in which consumption power
is suppressed extremely.
When a battery which has been charged is newly mounted in the
information processing unit having the suspended mode or an
external power supply is connected thereto in the suspended mode,
the information processing apparatus can be returned to the usual
operation again.
When a battery which has been charged is not mounted in the
information processing unit having the suspended mode or an
external power supply is not connected thereto in the suspended
mode, switching control means examines in accordance with the kind
of battery detected by the kind-of-battery detection means whether
the output voltage of the battery being discharged reaches a
previously set termination voltage which is different depending on
the kind of battery.
As the result that the switching control means examines the output
voltage of the battery being discharged, when the output voltage of
the battery being discharged reaches the termination voltage,
supply of electric power to the apparatus body including the
battery controller is stopped.
As described above, according to the battery controller, since the
battery is discharged in accordance with the previously set battery
switching voltage, suspended mode shift voltage and termination
voltage which are different depending on the detected kind of
battery, the capacity of the batteries of different kinds can be
used effectively and overdischarging can be prevented.
(2) In the battery controller described in the item (1), the
batteries of different kinds are charged.
The battery controller includes a constant current charging circuit
and a constant voltage charging circuit, for example, as battery
charging means for charging the batteries of different kinds and
controls charging in combination of the two charging circuits.
When the external power supply is connected after supply of
electric power by the battery, the charge control means operates
the battery charging means in accordance with the kind of battery
detected by the kind-of-battery detection means and the battery is
charged in combination of the constant current charging circuit and
the constant voltage charging circuit.
For example, when the battery the kind of which is detected by the
kind-of-battery detection means is an NiMH battery, the constant
current charging is made in which the constant current charging
circuit of the battery charging means is used to charge the battery
by a rapid charging current recommended by a battery maker and a
temperature of the battery is detected by means of the thermistor
terminal to terminate the charging.
Further, when the battery the kind of which is detected by the
kind-of-battery detection means is an Li ion battery, the constant
current and constant voltage charging is made in which the constant
current charging circuit and the constant voltage charging circuit
of the battery charging means are used to first charge the battery
by the constant current and then switch the constant current
charging to the constant voltage charging when a terminal voltage
of the battery reaches a predetermined value and after an elapse of
a predetermined time the charging is finished.
As described above, according to the battery controller, since the
kind of battery is detected to control charging of the battery in
combination of the constant current charging and the constant
voltage charging, batteries of different kinds can be charged.
(3) In the battery controller described in the items (1) and (2),
the total remaining operation time of the battery being discharged
and the battery not discharged is calculated.
When remaining operation time calculation means is started in case
where an apparatus including the battery controller is operated,
the remaining operation time calculation means requires data
relative to the remaining capacity and the remaining operation time
of a plurality of batteries to battery monitoring means of the
plurality of batteries.
When the remaining operation time calculation means receives the
data from the battery monitoring means of the plurality of
batteries, the remaining operation time calculation means uses the
data relative to the remaining capacity and the remaining operation
time of the batteries being discharged to calculate the remaining
operation time of the batteries not discharged.
The remaining operation time calculation means adds the remaining
operation time of the battery being discharged obtained from the
battery monitoring means and the calculated remaining operation
time of the battery not discharged to calculate the total remaining
operation time.
Since a battery monitoring IC included in the smart battery which
supports the standard specification "smart battery" uses an average
discharge current value to calculate the remaining operation time,
the remaining operation time in the unoperated state is largely
different from the remaining operation time in the discharging
operation.
Accordingly, the battery controller calculates the remaining
operation time of the battery not discharged on the basis of the
relation of the remaining capacity and the remaining operation time
of the battery being discharged.
As described above, according to the battery controller, since data
of the battery being discharged is used to calculate the remaining
operation time of the battery not discharged, the total remaining
operation time of the plurality of batteries can be calculated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram schematically illustrating a personal
computer equipped with a battery controller of the present
invention;
FIG. 2 is a perspective view showing an external appearance of the
personal computer;
FIG. 3 is a block diagram schematically illustrating the battery
controller of the present invention;
FIG. 4 is a block diagram illustrating a kind-of-battery detecting
operation provided by the battery controller of the present
invention;
FIG. 5 is a block diagram illustrating a battery discharge
switching operation and a termination voltage detecting operation
provided by the battery controller of the present invention;
FIG. 6 is a block diagram illustrating a smart battery data
obtaining operation provided by the battery controller of the
present invention;
FIG. 7 is a block diagram illustrating a remaining operation time
calculating process provided by the battery controller of the
present invention;
FIG. 8 is a block diagram illustrating an example of a battery
state display picture provided in the battery controller of the
present invention; and
FIG. 9 is a block diagram schematically illustrating a battery
controlling microcomputer provided in the battery controller of the
present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A battery controller according to an embodiment of the present
invention is now described in which a microcomputer for a keyboard
of a personal computer is used in combination therewith to charge
and discharge two different kinds of batteries and display a
remaining operation time of the batteries.
FIG. 1 is a schematic diagram illustrating a personal computer of
the embodiment. In FIG. 1, numeral 100 denotes a personal computer,
110 a CPU, 120 a memory, 121 an operating system, 122 an advanced
power management basic input/output system (hereinafter referred to
as APM-BIOS), 123 a system management bus basic input/output system
(hereinafter referred to as SMB-BIOS), 130 a magnetic disk unit,
131 a battery state display software, 140 a display unit, 141 a
battery state display picture, 150 a keyboard, 151 a microcomputer
for a keyboard, 160 a battery controller, and 161 and 162 smart
batteries.
As shown in FIG. 1, the personal computer of the embodiment
includes the CPU 110, the memory 120, the operating system 121, the
APM-BIOS 122, the SMB-BIOS 123, the magnetic disk unit 130, the
battery state display software 131, the display unit 140, the
battery state display picture 141, the keyboard 150, the
microcomputer 151 for the keyboard, the battery controller 160, and
the smart batteries 161 and 162.
Further, as shown in FIG. 1, in the personal computer 100 of the
embodiment, the CPU 110 for controlling the whole of the personal
computer 100, the memory 120 in which the operating system 121, the
APM-BIOS 122 and the SMB-BIOS 123 are stored, the magnetic disk
unit 130 in which the battery state display software 131 is stored,
the display unit 140 for displaying the battery state display
picture 141, the keyboard 150 including the keyboard microcomputer
151, and the battery controller 160 for controlling the smart
batteries 161 and 162 are connected.
The SMB-BIOS 123 stored in the memory 120 of the personal computer
100 is a basic input/output system (BIOS) for battery management
for supporting the standard specification "smart battery". Further,
the APM-BIOS 122 is a basic input/output system (BIOS) for power
management for supporting portion relative to the remaining
operating time of the battery management.
The battery state display software 131 stored in the magnetic disk
unit 130 of the personal computer 100 is a software which is
started by a user at the user's discretion to display the state of
the smart batteries 161 and 162 onto the battery state display
picture 141 of the display unit 140 on the basis of data obtained
from the smart batteries 161 and 162.
The smart batteries 161 and 162 controlled by the battery
controller 160 of the embodiment are batteries of different kinds
such as the NiMH battery and the Li ion battery which support the
standard specification "smart battery".
FIG. 2 shows the external appearance of the personal computer 100
of the embodiment.
As shown in FIG. 2, the personal computer 100 of the embodiment
includes two slots of first and second bays into which the smart
batteries 161 and 162 are mounted detachably. Either slot can
accommodate any battery of different kind.
Further, states of the smart batteries 161 and 162 mounted into the
first and second bays are displayed on the battery state display
picture 141 of the display unit 140 of the personal computer
100.
As shown in FIG. 2, since the personal computer 100 including the
battery controller 160 of the embodiment includes the first and
second bays into which the smart batteries 161 and 162 are mounted
detachably, two batteries can be mounted therein simultaneously, so
that the personal computer 100 can be operated for a long time by
the batteries.
FIG. 3 is a schematic diagram illustrating the battery controller
160 of the embodiment. In FIG. 3, numeral 310 denotes a battery
charging circuit, 311 a constant current charging circuit, 312 a
constant voltage charging circuit, 320 a charge control IC, 321 a
battery voltage detection circuit, 330 a kind-of-battery detection
circuit, 340 a discharge switching circuit, and 341 a termination
voltage detection circuit. The kind-of-battery detection circuit
330 is for detecting the kind of type of the battery used and is
never for discriminating different kinds of battery or the same
kind of battery.
As shown in FIG. 3, the battery controller 160 of the embodiment
includes the battery charging circuit 310, the constant current
charging circuit 311, the constant voltage charging circuit 312,
the charge control IC 320, the battery voltage detection circuit
321, the kind-of-battery detection circuit 330, the discharge
switching circuit 340, and the termination voltage detection
circuit 341.
Further, as shown in FIG. 3, in the battery controller 160 of the
embodiment, the microcomputer 151 for the keyboard is used as a
host LSI of the standard specification "smart battery" and controls
the smart batteries 161 and 162 by connecting the charge control IC
320, the battery voltage detection circuit 321, the kind-of-battery
detection circuit 330 and the discharge switching circuit 340.
The battery charging circuit 310 of the battery controller 160 of
the embodiment includes the constant current charging circuit 311
and the constant voltage charging circuit 312 and can charge
batteries of different kinds.
The charge control IC 320 of the battery controller 160 of the
embodiment controls the constant current charging circuit 311 or
the constant voltage charging circuit 312 of the battery charging
circuit 310 in accordance with a signal from the battery voltage
detection circuit 321 to charge the smart batteries 161 and
162.
The kind-of-battery detection circuit 330 of the battery controller
160 of the embodiment detects a kind of battery by means of
thermistor terminals of the smart batteries 161 and 162.
The discharge switching circuit 340 of the battery controller 160
of the embodiment measures discharge voltages of the smart
batteries 161 and 162 and switches a discharge battery for
supplying electric power to the personal computer 100 in accordance
with a voltage value thereof.
Further, the termination voltage detection circuit 341 of the
discharge switching circuit 340 measures discharge voltages of the
smart batteries 161 and 162 and shifts the operation of the
personal computer 100 to a suspended mode in accordance with a
voltage value thereof.
FIG. 4 illustrates the kind-of-battery detection operation of the
battery controller 160 of the embodiment. In FIG. 4, numerals 401
and 402 denote thermistor terminals, and 410 a comparison circuit
for comparing outputs of the thermistor terminals.
As shown in FIG. 4, the kind-of-battery detection operation of the
battery controller 160 of the embodiment is performed by means of
the thermistor terminals 401 and 402 and the comparison circuit 410
for comparing the outputs of the thermistor terminals.
Further, as shown in FIG. 4, in the kind-of-battery detection
operation of the battery controller 160 of the embodiment,
impedances of the thermistor terminals 401 and 402 provided in the
smart batteries 161 and 162 are measured and the measured impedance
values are compared in the comparison circuit 410 to detect the
kinds of the batteries.
The thermistor terminals 401 and 402 of the smart batteries 161 and
162 are provided to detect temperatures of the smart batteries 161
and 162 and particularly are used to detect completion of charging
of the NiMH battery.
More particularly, the output of the thermistor terminal of the
NiMH battery is varied in accordance with a temperature at a high
impedance while the output of the thermistor terminal of the Li ion
battery is constant at a low impedance and accordingly when the
NiMH battery and the Li ion battery are used as the smart batteries
161 and 162, the impedances of the thermistor terminals 401 and 402
can be measured to thereby detect the kinds of the batteries.
FIG. 5 illustrates the discharge switching operation and the
termination voltage detection operation of the battery controller
160 of the embodiment. In FIG. 5, numerals 501 and 502 denote
battery voltage terminals, 510 a discharge voltage comparison
circuit and 511 a termination voltage comparison circuit.
As shown in FIG. 5, the discharge switching operation and the
termination detection operation of the battery controller 160 of
the embodiment are performed by means of the battery voltage
terminals 501 and 502, the discharge voltage comparison circuit 510
and the termination voltage comparison circuit 511.
Further, as shown in FIG. 5, in the discharge switching operation
and the termination voltage detection operation of the battery
controller 160 of the embodiment, output voltages of the battery
voltage terminals 501 and 502 of the smart batteries 161 and 162
are measured, so that switching of the battery for discharging or
shift to the suspended mode is performed by means of the discharge
voltage comparison circuit 510 and the termination voltage
comparison circuit 511.
The discharge voltage comparison circuit 510 of the discharge
switching circuit 340 compares the output voltages from the battery
voltage terminals 501 and 502 of the smart batteries 161 and 162 in
accordance with a detection result from the kind-of-battery
detection circuit 330 to judge whether a voltage value for
switching the discharging battery is reached or not.
Further, the discharge voltage comparison circuit 510 of the
discharge switching circuit 340 compares the output voltages from
the battery voltage terminals 501 and 502 of the smart batteries
161 and 162 in accordance with the detection result from the
kind-of-battery detection circuit 330 to judge whether the very low
battery voltage for shifting the personal computer 100 to the
suspended mode is reached or not.
The termination voltage comparison circuit 511 of the termination
voltage detection circuit 341 compares the output voltages from the
battery voltage terminals 501 and 502 of the smart batteries 161
and 162 in accordance with the detection result from the
kind-of-battery detection circuit 330 to judge whether a voltage
value for shifting to the suspended mode is reached or not.
FIG. 6 illustrates the smart battery data obtaining operation of
the battery controller of the embodiment. In FIG. 6, numerals 601
and 602 denotes battery monitoring ICs, 610 a system management
bus, 611 a clock line, 620 a smart battery data, and 630 a
remaining operation time calculation unit.
As shown in FIG. 6, the smart battery data obtaining operation of
the battery controller 160 of the embodiment is performed by means
of the battery monitoring ICs 601 and 602, the system management
bus 610, the clock line 611, the smart battery data 620 and the
remaining operation time calculation unit 630.
Further, as shown in FIG. 6, in the smart battery data obtaining
operation of the battery controller 160 of the embodiment, the
smart batteries 161 and 162 and the microcomputer 151 for the
keyboard are connected by means of the system management bus 610
and the clock line 611 is switched to thereby obtain the smart
battery data 620.
In the battery controller 160 of the embodiment, the battery
monitoring ICs 601 and 602 included in the smart batteries 161 and
162 are ICs defined in the standard specification "smart battery"
and which serve to detect terminal voltage, discharging/charging
currents, temperatures of battery cells and the like of the smart
batteries 161 and 162.
The smart battery data 620 of the battery controller 160 of the
embodiment include data indicative of states of the smart batteries
161 and 162 produced by the battery monitoring ICs 601 and 602 and
the like. The smart battery data 620 include, for example, data
such as the "average current data" indicative of an average
discharging current in one minute, the average time to empty data"
indicative of a remaining operation time until a remaining amount
of the battery is reduced to zero at the average discharging
current and the "remaining capacity data" indicative of a remaining
capacity of the battery.
The remaining operation time calculation unit 630 of the battery
state display software 131 uses the smart battery data 620 to
calculate the total remaining operation time of the plurality of
smart batteries 161 and 162.
Description is now made to operation for performing charging,
discharging and display of the remaining operation time of the
smart batteries 161 and 162 of different kinds in the personal
computer 100 including the battery controller 160 of the embodiment
in combination with the microcomputer 151 for the keyboard.
In the personal computer 100 including the battery controller 160
of the embodiment, the microcomputer 151 for the keyboard performs
polling by means of the system management bus 610 and examines
whether the smart batteries 161 and 162 are mounted in the first or
second bay.
When the microcomputer 151 for the keyboard detects that the
battery is mounted in any of the first or second bay, the mounted
battery is set as the discharge battery. When the batteries are
mounted in both of the bays, the battery mounted in the first bay
is set as the discharge battery and flag information indicating
which of batteries is being discharged is set.
The kind-of-battery detection circuit 330 of the battery controller
160 of the embodiment measures impedances of the thermistor
terminals 401 and 402 of the smart batteries 161 and 162 and
produces different signals in accordance with the measured
impedance values as kind-of-battery detection signals.
The discharge switching circuit 340 of the battery controller 160
of the embodiment supplies the kind-of-battery detection signal
produced by the kind-of-battery detection circuit 30 and the output
voltage from the battery voltage terminal 501 or 502 of the smart
battery 161 or 162 set in the discharge battery by the
microcomputer 151 for the keyboard to the discharge voltage
comparison circuit 510.
The discharge voltage comparison circuit 510 of the discharge
switching circuit 340 sets the low battery voltage in accordance
with the kind-of-battery detection signal produced by the
kind-of-battery detection circuit 330 and examines whether the
output voltage of the battery being discharged reaches the low
battery voltage or not.
The low battery voltage is a voltage for switching the battery. In
the battery controller 160 of the embodiment, when the output
voltage of the smart battery 161 being discharged reaches the low
battery voltage, the smart battery 161 is switched or changed to
the smart battery 162, so that the smart battery 162 is
discharged.
As the result that the discharge voltage comparison circuit 510 of
the discharge switching circuit 340 examines the output voltage of
the battery being discharged, when the output voltage of the
battery being discharged reaches the low battery voltage, the
battery to be discharged is switched to the battery mounted in the
second bay and flag information indicating which battery is being
discharged is changed to indicate the battery mounted in the second
bay.
Further, when any battery is not mounted in the second bay in case
where the battery being discharged is switched, the battery being
discharged continues to be discharged even after the output voltage
of the battery being discharged reaches the low battery
voltage.
As described above, when the battery being discharged continues to
be discharged even after the output voltage of the battery being
discharged reaches the low battery voltage, the discharge voltage
comparison circuit 510 of the discharge switching circuit 340 sets
the very low battery voltage in accordance with the kind-of-battery
detection signal produced by the kind-of-battery detection circuit
330 and examines whether the output voltage of the battery being
discharged reaches the very low battery voltage or not.
As the result that the discharge voltage comparison circuit 510 of
the discharge switching circuit 340 examines the output voltage of
the battery being discharged, when the output voltage of the
battery being discharged reaches the very low battery voltage, a
signal for shifting the personal computer 100 to the suspended mode
is produced.
When the personal computer 100 receives the signal for shifting the
personal computer 100 to the suspended mode, the personal computer
100 turns off the backlight of the display unit 140 and stops the
usual operation so that the personal computer is shifted to the
mode in which the consumption power is suppressed extremely.
In the suspended mode, when the battery which has been charged
completely is newly mounted in the bay in which the battery is not
discharged or an external power supply is connected, the personal
computer 100 can be returned to the usual operation again.
In the suspended mode, when the battery which has been charged
completely is not mounted or the external power supply is not
connected, the termination voltage comparison circuit 511 of the
termination voltage detection circuit 341 sets the termination
voltage in accordance with the kind-of-battery detection signal
produced by the kind-of-battery detection circuit 330 and examines
whether the output voltage of the battery being discharged reaches
the termination voltage or not.
As the result that the termination voltage comparison circuit 511
of the termination voltage detection circuit 341 examines the
output voltage of the battery being discharged, when the output
voltage of the battery being discharged reaches the termination
voltage, supply of electric power to the personal computer 100 is
stopped.
When the external power supply is connected after electric power is
supplied by the discharge battery as described above, the charge
control IC 320 of the battery controller 160 of the embodiment
operates the constant current charging circuit 311 or the constant
voltage charging circuit 312 in accordance with the kind-of-battery
detection signal from the kind-of-battery detection circuit 330 to
start charging of the smart batteries 161 and 162.
Further, when the batteries are charged by the constant voltage
charging circuit 312, the charge control IC 320 of the battery
controller 160 of the embodiment controls the charge voltage of the
battery charging circuit 310 in accordance with the signal from the
battery voltage detection circuit 321 to charge the smart batteries
161 and 162.
As described above, in the battery controller 160 of the
embodiment, the kind of the smart batteries 161 and 162 is detected
by the kind-of-battery detection circuit 330 and discharge or
charge is made in accordance with the kind-of-battery detection
signal, while the battery detected by the kind-of-battery detection
circuit 330 may be any battery equipped with the thermistor
terminal 401 or 402 from which the kind of the battery can be
detected and is not necessarily required to be a battery which
supports the standard specification "smart battery".
When the battery state display software 131 is started while the
personal computer 100 including the battery controller 160 of the
embodiment is operated, the remaining operation time calculation
unit 630 of the battery state display software 131 requires the
smart battery data 620 to the microcomputer 151 for the keyboard
through the operating system 121, the APM-BIOS 122 and the SMB-BIOS
123.
The microcomputer 151 for the keyboard switches the clock line 611
and obtains the smart battery data 620 of the smart batteries 161
and 162 from the battery monitoring ICs 601 and 602 through the
system management bus 610.
The smart battery data 620 of the battery controller 160 of the
embodiment include data such as the average discharge current, the
remaining operation time and the remaining capacity as described
above.
FIG. 7 illustrates the remaining operation time calculation process
of the battery controller 160 of the embodiment.
As shown in FIG. 7, in the remaining operation time calculation
process of the battery controller 160 of the embodiment, the
remaining capacity and the remaining operation time of the smart
battery 161 being discharged and the remaining capacity of the
smart battery 162 not discharged are used to calculate the
remaining operation time of the smart battery 162 not discharged
and calculate the total remaining operation time of the smart
batteries 161 and 162.
As described above, the battery monitoring ICs 601 and 602 included
in the smart batteries 161 and 162 report the respective remaining
operation times to the microcomputer 151 for the keyboard which is
the host LSI as the smart battery data 620.
However, since the average discharge current value of the smart
battery 162 not discharged is very small, the remaining operation
time reported by the battery monitoring IC 602 of the smart battery
162 not discharged has an extremely large value.
Accordingly, even if the respective remaining operation times sent
from the battery monitoring ICs 601 and 602 are added together, the
exact total remaining operation time of the smart batteries 161 and
162 cannot be obtained.
Thus, as shown in FIG. 7, the remaining operation time calculation
unit 630 of the battery state display software 131 calculates the
remaining operation time "84 minutes" from a ratio of the remaining
capacity "1000 mAh" and the remaining operation time "30 minutes"
of the smart battery 161 being discharged and the remaining
capacity "2800 mAh" of the smart battery 162 not discharged and
adds the remaining operation time "30 minutes" of the smart battery
161 to the remaining operation time "84 minutes" of the smart
battery 162 to obtain the total remaining operation time "114
minutes".
The calculation of the total remaining operation time is made when
one of the batteries is being discharged, while even when electric
power is supplied by the external power supply and both of the
batteries are not discharged, the total remaining operation time
can be calculated by memorizing the remaining capacity and the
remaining operation time during supply of electric power by the
battery.
FIG. 8 shows an example of the battery state display picture 141 of
the battery controller 160 of the embodiment.
As shown in FIG. 8, the state of supplying electric power, the
total remaining operation time and the respective remaining
capacities of the batteries calculated by the remaining operation
time calculation unit 630 of the battery state display software 131
are displayed in the battery state display picture 141 of the
battery controller 160 of the embodiment.
Further, in the battery controller 160 of the embodiment, the
battery control microcomputer may be used to make charging and
discharging of the batteries of different kinds and display of the
remaining operation time.
FIG. 9 schematically illustrates the battery control microcomputer
of the battery controller 160 of the embodiment. In FIG. 9, numeral
900 denotes a battery control microcomputer, 901 a host LSI unit,
902 a charge control unit, 903 a voltage control unit, 904 a
discharge switching control unit, 905 a host interface, and 906 an
LCD indicator interface.
As shown in FIG. 9, the battery control microcomputer of the
battery controller 160 of the embodiment includes the host LSI unit
901, the charge control unit 902, the voltage control unit 903, the
discharge switching control unit 904, the host interface 905 and
the LCD indicator interface 906.
Further, as shown in FIG. 9, the battery control microcomputer 900
of the battery controller 160 of the embodiment is connected to the
battery charging circuit 310, the smart batteries 161 and 162 and
the microcomputer 151 for the keyboard, and the host LSI unit 901
of the battery control microcomputer 900 is connected to the charge
control unit 902, the voltage control unit 903, the discharge
switching control unit 904, the host interface 905 and the LCD
indicator interface 906.
The host LSI unit 901 of the battery control microcomputer 900
corresponds to the host LSI of the standard specification "smart
battery". The host LSI unit controls the whole of the battery
control microcomputer 900 and detects a kind of the battery on the
basis of the smart battery data 620 obtained from the smart
batteries 161 and 162.
The charge control unit 902 of the battery control microcomputer
900 controls the constant current charging circuit 311 or the
constant voltage charging circuit 312 of the battery charging
circuit 310 in accordance with the signal from the voltage control
unit 903 to charge the smart batteries 161 and 162.
The discharge switching control unit 904 of the battery control
microcomputer 900 measures discharge voltages of the smart
batteries 161 and 162 and switches the discharge battery for
supplying electric power to the personal computer 100 in accordance
with the measured voltage value.
Further, the discharge switching control unit 904 of the battery
control microcomputer 900 shifts the personal computer 100 to the
suspended mode in accordance with the discharge voltage values of
the smart batteries 161 and 162.
The host interface 905 of the battery control microcomputer 900 is
an interface for sending the smart battery data 620 through the
microcomputer for the keyboard to the battery state display
software 131.
The LCD indicator interface 906 of the battery control
microcomputer 900 is an interface used to display the smart battery
data 620 onto the LCD.
As described above, according to the battery controller of the
embodiment, since the battery switching voltage, the suspended mode
shift voltage and the termination voltage which have different
values in accordance with the detected kind of the battery and are
previously set are utilized to make discharging, the capacity of
the battery of different kind can be used effectively and
overdischarging can be prevented.
Further, according to the battery controller of the embodiment,
since charging is made in combination of the constant current
charging and the constant voltage charging operation in accordance
with the detected kind of the battery, the battery of different
kind can be charged effectively.
In addition, according to the battery controller of the embodiment,
since the data of the battery being discharged is used to calculate
the remaining operation time of the battery not discharged, the
total remaining operation time of the plurality of batteries can be
calculated.
Although the present invention has been described definitely with
reference to the embodiment, the present invention is not limited
to the embodiment and it is a matter of course that various changes
and modifications may be made without departing from the spirit and
scope thereof.
Brief description of the effects obtained by representative aspects
disclosed in the present invention is as follows:
(1) Since the battery switching voltage, the suspended mode shift
voltage and the termination voltage which have different values in
accordance with the detected kind of the battery and are previously
set are utilized to make discharging, the capacity of the battery
of different kind can be used effectively and overdischarging can
be prevented.
(2) Since charging is controlled in combination of the constant
current charging and the constant voltage charging operation in
accordance with the detected kind of the battery, the battery of
different kind can be charged effectively.
(3) Since the data of the battery being discharged is used to
calculate the remaining operation time of the battery not
discharged, the total remaining operation time of the plurality of
batteries can be calculated.
* * * * *